Hi, I hope you can help me. I am a physicist but not a researcher and have currently not the time to study many papers about the subject of dark matter. What I would need for deeper thoughts is an expansion in a series of the Newton law for cases where it has been measured that star rotation around a galaxy is in contrast to Newton. Meaning: There should be something like F ≈ 1/r^2 + a/r^3 + ... I understand fully that the answer can't be that simple but please provide me with some information about the measured values and the uncertaincy in those measurements. Thanks a lot in advance. Best regards, Jens PS, I edit this post: It ist not that I want to push a simple MOND hypothesis, I need reliable experimental data. Thanks a lot.